The development of the semiconductor industry has continuously increased requirements of the high density integrated circuits during the past years due to their smaller area, higher operation frequency and other benefits. No matter the central processing unit (CPU), the graphic processing unit (GPU), the integrated circuits applied on the wireless products such as microwave/millmeter communication or ultra-high frequency (UHV) communication, or other integrated circuits.
Besides the approach of directly shrinking the critical dimension (CD), such as the finFET and the carbon nanotube developed recently, another approach is to transmit signs between numerous elements and/or terminals by using the multilayered integration technology. For example, both the thin-film mirostrips (TFMSs) and the complementary-conducting-strip (CCS) are the technologies used to form the signal lines for the monolithic microwave integrated circuit (MMIC) or other applications. Nevertheless, all currently available technologies still has to be improved for saving the wafer area, reducing interference, enhancing heat dissipation, increasing design flexibility, and so on.
Accordingly, it is desired to improve the current technologies or develop new technologies for further develop and achieve high density integrated circuits, especially when the commercial applications required integrated circuits with more density and more efficiency.